When a bone fracture is incurred, a number of general steps are followed to enhance healing. The bone is generally reduced in a manner that involves realigning segments of the bone into their respective anatomical locations, to ensure proper alignment and healing of the bone. The bone is then immobilized to prevent the pieces of the bone from shifting during the healing process. Immobilization may involve the use of casts or splints to hold the bones in place, generally for two to eight weeks depending on the severity and location of the break. In certain instances, traction is employed using tension to prevent the bones from shortening. In certain fractures involving long bones, traction is used to counteract large muscles that tend to pull the bone out of place. Severe cases may also require surgery with implants to keep the bones aligned during the healing process. These situations use plates and screws along with the casts to immobilize the bone.
Bone fractures and their treatment may vary greatly depending upon the bone and the patient. One type involves fracture of the tibia in children, which can be difficult to address in that the tibia is a load-bearing bone, and in that the growth plates of the tibia should be left intact. Misalignment of the tibia can lead to pain when force is placed on the bone, and can also affect the patient's gait. Similar issues can exist with other bones, such as the clavicle.
Previous techniques used for reduction and immobilization of the tibia have involved entry via an upper portion of the tibia for adults, and the use of flexible nails for pediatric patients in order to avoid growth plates. While these approaches have been useful, they can be challenging to implement in a manner that addresses the needs of the stent application. For example, when a fracture is not in the middle third of the tibia, providing a stent that appropriately supports the bone near the fracture can be difficult, particularly with pediatric patients. As another example, rotational fixation can be difficult to achieve. Furthermore, if a stent is improperly inserted or aligned, the tibial fracture can be improperly aligned, which can result in improper healing.
These and other matters have presented challenges to the treatment of bone fractures, for a variety of applications.